1. Field of the Invention
The present invention relates to floor plans.
2. Description of the Prior Art
Floor plans of existing buildings were traditionally measured using a tape measure. The emergence of handheld measuring devices equipped with sensors now makes it possible to make measurements and transfer these measurements directly to specialized drawing software. An example of handheld measuring devices includes laser range finders, which send a laser pulse in a narrow beam towards the object and measure the time taken by the pulse to be reflected off the target and returned to the device. An example of a handheld device is the Disto, which is a laser distance finder that transmits measurements wirelessly to software running on a remote computer.
Many factors influence the precision of measurements made by a sensor: the quality of the device components, the precision of the assembly, the qualifications of the operator, the care taken while manipulating the device, the environmental conditions during the operation such as the presence of furniture, the loss of precision during data transmission or subsequent computations, and limitations due to the inner workings of the sensor. These factors can be grouped into two categories: those inherent to the sensor, which can be approximated using a sensor error model, and those related to operating conditions, which can be approximated using an operation error model.
An example of error source inherent to a sensor is gyroscopic drift, which can be approximated using an error model. Over short periods of time, angles measured using a gyroscope tend to drift at a nearly constant rate.
Using measurements made by angular sensors to draw a floor plan may also introduce a scale uncertainty. In fact, knowing the angles between all segments of a floor plan is insufficient to determine the distance between two points.
Obtaining a consistent and satisfying floor plan based on real life measurements is a challenge. For instance, one might want to compensate measures for measurement errors while keeping some angles square and some walls parallel. Greater sensor imprecision implies greater error compensation and makes floor plan consistency more difficult to maintain. One might also want to compensate for imperfections in the building being measured, such as the compression or expansion of construction materials over time, deformation due to tensions in the structure, movements caused by environmental forces such as wind, water or ground movements, or simply construction errors that were made when the building was built or repaired.
In many circumstances, a highly accurate floor plan may appear crooked to the reader, as it makes non-square angles and non-parallel walls stand out. An idealized version of the floor plan may then prove more useful in these cases.